"The last four or five outings, it's just slowly sliding downhill," Arroyo said. "The last three, how I won all three, I have no idea. It's been tough the last three games not knowing if I can get back out there inning by inning."

"I've pitched through this in the past, but it's as bad as it's ever been."

The pain is eroding Arroyo's velocity, which was deteriorating before the injury.

"When I was throwing 83-87 mph, it was manageable," the 12-year veteran said. "But I'm throwing the ball 80-84 -- and 84 is when I'm sexy, you know, which is ridiculous. It's just too difficult to get big-league hitters out with that velocity time and time and time again."

Arroyo and Gibson said that the pitcher will receive an MRI soon, then discuss their next move. But Arroyo -- who won the World Series with the Boston Red Sox in 2004 -- sees the end of his career approaching with supersonic speed.

"It's just getting to the point where there's too much pain," the right-hander said. "I've got 17 more starts, or something like that, and I can't continue doing this for that long.

"I've been trying to avoid this for 20 years but I'll be facing the inevitable for the first time in two decades."

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